Use of digestate as an alternative to mineral fertilizer: effects on growth and crop quality

Nowadays, the recycling of organic wastes represents a key factor for improving soil and crop quality with socio-economic and environmental benefits. In recent years, the production of digestate significantly increased with a crescent need to be sustainable disposal. The use of digestate as soil amendment has been widely studied but few researches evaluated the digestate effects on crop quality. Since it has been proven that digestate increased soil fertility, we hypothesized that it could increase crop quality as organic fertilizers do. To verify this hypothesis, we analyzed the effects of two digestates on Cucumber quality. Cucumber was chosen because it is an important old crop used worldwide as fresh food, and in cosmetic and pharmaceutic industries. Results showed that digestates increased its content of phenols and flavonoids with antioxidant activity. Neohesperidine and hesperitin with well-known antioxidant, anti-inflammatory and anti-carcinogenic properties as well as naringin and narirutin with the power of reducing the risk of atherosclerosis and cardiovascular complications were manifested only in digestate amended cucumbers. These results highlighted the potentiality of digestates not only as crop growth promoter but also as phytochemical inducers representing a good option for the production of high-quality food with reduced chemical mineral fertilizer inputs.